Collected Evidence: Collected Evidence: Buffer in-field ponds We have captured no evidence for the effects of buffering in-field ponds on farmland wildlife. 'No evidence' for an action means we have not yet found any studies that directly and quantitatively tested this action during our systematic journal and report searches. Therefore we have been unable to assess whether or not the action is effective or has any harmful impacts. Please get in touch if you know of such a study for this action.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F97https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F97Mon, 24 Oct 2011 21:48:25 +0100Collected Evidence: Collected Evidence: Brown and black bullheads: Application of a biocide A study in the UK reported that use of a piscicide containing rotenone achieved eradication of black bullhead. A study in the USA found that rotenone successfully eradicated black bullhead, but one of two ponds required two separate doses.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1050https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1050Wed, 07 Oct 2015 10:41:27 +0100Collected Evidence: Collected Evidence: Brown and black bullheads: Netting A replicated study from 1999-2000 in shallow interconnected ponds in a nature reserve in Belgium1 found that double fyke nets could be used to significantly reduce the population of brown bullhead measuring over 8cm  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1051https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1051Wed, 07 Oct 2015 10:51:53 +0100Collected Evidence: Collected Evidence: Brown and black bullheads: Biological control using native predators No evidence was found on the impact of native predators on invasive bullhead populations. 'No evidence' for an action means we have not yet found any studies that directly and quantitatively tested this action during our systematic journal and report searches. Therefore we have been unable to assess whether or not the action is effective or has any harmful impacts. Please get in touch if you know of such a study for this action.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1053https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1053Sun, 11 Oct 2015 20:12:08 +0100Collected Evidence: Collected Evidence: Brown and black bullheads: Biological control of beneficial species No evidence was found for reducing or controlling bullhead population size by reducing the population of co-occurring beneficial species. 'No evidence' for an action means we have not yet found any studies that directly and quantitatively tested this action during our systematic journal and report searches. Therefore we have been unable to assess whether or not the action is effective or has any harmful impacts. Please get in touch if you know of such a study for this action.    Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1076https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1076Tue, 13 Oct 2015 12:59:42 +0100Collected Evidence: Collected Evidence: Brown and black bullheads: Habitat manipulation No evidence was captured on the impact of habitat manipulation on invasive bullhead populations. 'No evidence' for an action means we have not yet found any studies that directly and quantitatively tested this action during our systematic journal and report searches. Therefore we have been unable to assess whether or not the action is effective or has any harmful impacts. Please get in touch if you know of such a study for this action.    Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1077https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1077Tue, 13 Oct 2015 13:02:26 +0100Collected Evidence: Collected Evidence: Brown and black bullheads: Draining invaded waterbodies No evidence was found for use of draining invaded waterbodies to reduce the population size of invasive bullheads. 'No evidence' for an action means we have not yet found any studies that directly and quantitatively tested this action during our systematic journal and report searches. Therefore we have been unable to assess whether or not the action is effective or has any harmful impacts. Please get in touch if you know of such a study for this action.    Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1078https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1078Tue, 13 Oct 2015 13:03:40 +0100Collected Evidence: Collected Evidence: Brown and black bullheads: Electrofishing No evidence was found for use of electrofishing to reduce the population size of invasive bullheads. 'No evidence' for an action means we have not yet found any studies that directly and quantitatively tested this action during our systematic journal and report searches. Therefore we have been unable to assess whether or not the action is effective or has any harmful impacts. Please get in touch if you know of such a study for this action.      Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1079https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1079Tue, 13 Oct 2015 13:05:15 +0100Collected Evidence: Collected Evidence: Brown and black bullheads: Using a combination of netting and electrofishing No evidence was captured on the impact of electrofishing and gill netting combined on bullhead populations. 'No evidence' for an action means we have not yet found any studies that directly and quantitatively tested this action during our systematic journal and report searches. Therefore we have been unable to assess whether or not the action is effective or has any harmful impacts. Please get in touch if you know of such a study for this action.    Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1080https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1080Tue, 13 Oct 2015 13:08:24 +0100Collected Evidence: Collected Evidence: Brown and black bullheads: Trapping using sound or pheromonal lures No evidence has been found for the effectiveness of trapping bullheads using sound or pheromonal lures. 'No evidence' for an action means we have not yet found any studies that directly and quantitatively tested this action during our systematic journal and report searches. Therefore we have been unable to assess whether or not the action is effective or has any harmful impacts. Please get in touch if you know of such a study for this action.    Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1081https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1081Tue, 13 Oct 2015 13:09:55 +0100Collected Evidence: Collected Evidence: Brown and black bullheads: Increasing carbon dioxide concentrations No evidence was captured on the use of carbon dioxide for management of invasive bullheads. 'No evidence' for an action means we have not yet found any studies that directly and quantitatively tested this action during our systematic journal and report searches. Therefore we have been unable to assess whether or not the action is effective or has any harmful impacts. Please get in touch if you know of such a study for this action.    Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1082https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1082Tue, 13 Oct 2015 13:11:25 +0100Collected Evidence: Collected Evidence: Brown and black bullheads: UV radiation No evidence was captured on the impact of UV radiation on bullhead populations. 'No evidence' for an action means we have not yet found any studies that directly and quantitatively tested this action during our systematic journal and report searches. Therefore we have been unable to assess whether or not the action is effective or has any harmful impacts. Please get in touch if you know of such a study for this action.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1083https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1083Tue, 13 Oct 2015 13:12:37 +0100Collected Evidence: Collected Evidence: Brown and black bullheads: Changing salinity No evidence was captured on the impact of changing salinity on bullhead populations. 'No evidence' for an action means we have not yet found any studies that directly and quantitatively tested this action during our systematic journal and report searches. Therefore we have been unable to assess whether or not the action is effective or has any harmful impacts. Please get in touch if you know of such a study for this action.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1084https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1084Tue, 13 Oct 2015 13:13:42 +0100Collected Evidence: Collected Evidence: Brown and black bullheads: Changing pH No evidence was captured on the impact of altering pH on bullhead populations. 'No evidence' for an action means we have not yet found any studies that directly and quantitatively tested this action during our systematic journal and report searches. Therefore we have been unable to assess whether or not the action is effective or has any harmful impacts. Please get in touch if you know of such a study for this action.    Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1085https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1085Tue, 13 Oct 2015 13:14:53 +0100Collected Evidence: Collected Evidence: Brown and black bullheads: Public education No evidence was captured on the impact of education programmes on invasive bullhead populations. 'No evidence' for an action means we have not yet found any studies that directly and quantitatively tested this action during our systematic journal and report searches. Therefore we have been unable to assess whether or not the action is effective or has any harmful impacts. Please get in touch if you know of such a study for this action.    Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1086https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1086Tue, 13 Oct 2015 13:15:46 +0100Collected Evidence: Collected Evidence: Build bird-perches to enhance natural seed dispersal One replicated, randomized, controlled study in Brazil found that building perches for birds increased species richness and abundance of new tree seedlings.  Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1245https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1245Fri, 03 Jun 2016 11:06:15 +0100Collected Evidence: Collected Evidence: Build bird perches to encourage colonisation by plants One replicated, controlled study in South Africa found that building artificial bird perches increased the number of seeds at two sites, but no shrubs became established at either of these sites. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1702https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1702Mon, 23 Oct 2017 11:24:30 +0100Collected Evidence: Collected Evidence: Build barriers to protect peatlands from the sea We found no studies that evaluated the effects, on peatland vegetation, of building barriers to protect peatlands from seawater damage. ‘We found no studies’ means that we have not yet found any studies that have directly evaluated this action during our systematic journal and report searches. Therefore we have been unable to assess whether or not the action is effective or has any harmful impacts. Please get in touch if you know of such a study for this action.Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1794https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1794Tue, 28 Nov 2017 08:19:42 +0000Collected Evidence: Collected Evidence: Build artificial bird perches to encourage seed dispersal One study evaluated the effects on peatland vegetation of building artificial bird perches. The study was in a tropical peat swamp. Vegetation cover (1 study): One replicated, paired, controlled study in a peat swamp forest in Indonesia found that artificial bird perches had no significant effect on seedling abundance. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1817https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F1817Tue, 28 Nov 2017 08:44:19 +0000Collected Evidence: Collected Evidence: Build fences around protected areas Two studies evaluated the effects on mammals of building fences around protected areas. One study was in Kenya and one was in Mozambique. COMMUNITY RESPONSE (1 STUDY) Richness/diversity (1 study): A before-and-after study in Kenya found that after a fence was built around a protected area, mammal species richness initially increased in both study sites, but subsequently declined at one of the sites. POPULATION RESPONSE (2 STUDIES) Abundance (2 studies): A paired sites study in Mozambique found that inside a fenced sanctuary there were more mammal scats than outside the sanctuary. A before-and-after study in Kenya found that after a fence was built around a protected area, mammal abundance initially increased in both study sites, but it subsequently declined at one of the sites. BEHAVIOUR (0 STUDIES)Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2561https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F2561Tue, 09 Jun 2020 12:38:38 +0100Collected Evidence: Collected Evidence: Build barriers to protect littoral areas from boat wakesWe found no studies that evaluated the effects, on vegetation, of building barriers to protect littoral marshes or swamps from boat wakes.   ‘We found no studies’ means that we have not yet found any studies that have directly evaluated this action during our systematic journal and report searches. Therefore we have been unable to assess whether or not the action is effective or has any harmful impacts. Please get in touch if you know of such a study for this action.Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3021https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3021Wed, 31 Mar 2021 14:41:04 +0100Collected Evidence: Collected Evidence: Build barriers to protect littoral freshwater marshes from rising water levels and severe weatherWe found no studies that evaluated the effects, on vegetation, of building barriers to protect littoral freshwater marshes from rising water levels and severe weather.   ‘We found no studies’ means that we have not yet found any studies that have directly evaluated this action during our systematic journal and report searches. Therefore we have been unable to assess whether or not the action is effective or has any harmful impacts. Please get in touch if you know of such a study for this action.Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3181https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3181Tue, 06 Apr 2021 16:13:34 +0100Collected Evidence: Collected Evidence: Build barriers to protect littoral brackish/salt marshes from rising water levels and severe weather Five studies evaluated the effects, on vegetation, of building barriers to protect littoral brackish/salt marshes from rising water levels and severe weather. Three studies were in the USA, one was in Italy and one was in the Netherlands. VEGETATION COMMUNITY Overall extent (3 studies): Two controlled studies (one also replicated, randomized, paired) in Italy and the USA found that protecting salt marshes with offshore structures had no significant effect on the seaward limit of emergent vegetation, after 17–27 months. It was similar, or retreated at a similar rate, in protected and unprotected marshes. One replicated, randomized, paired, controlled study in the USA found that brackish marshes protected with oyster shell reefs receded less, over one year, than unprotected marshes. Community composition (1 study): One replicated, site comparison study in the Netherlands reported that marshes protected with low sea walls had a similar overall plant community composition to nearby natural salt marshes, 15–22 years after the walls were built. Overall richness/diversity (2 studies): One controlled study in Italy reported that a salt marsh protected with an offshore fence contained more plant species, after 17 months, than an unfenced marsh. One replicated, site comparison study in the Netherlands recorded 85 plant and algal species across two salt marshes that had developed behind low sea walls, over 15–22 years, compared to 155 species recorded across multiple natural marshes in the region. VEGETATION ABUNDANCE Overall abundance (2 studies): Two controlled studies (one also replicated, randomized, paired) in Italy and the USA found that brackish/salt marshes protected with offshore structures contained a similar total amount of vegetation to unprotected marshes. This was true for cover and biomass. Individual species abundance (2 studies): One replicated, paired, site comparison study in the USA found that salt marshes protected with offshore breakwaters (and planted with cordgrasses Spartina spp.) typically contained less smooth cordgrass S. alterniflora, after 2–3 growing seasons, than nearby natural marshes. One replicated, site comparison study in the Netherlands reported that in marshes protected with low sea walls for 15–22 years and nearby natural salt marshes, the same plant species were the most frequent. VEGETATION STRUCTURE Height (1 study): One replicated, paired, site comparison study in the USA found that salt marshes protected with offshore breakwaters (and planted with cordgrasses Spartina spp.) contained shorter smooth cordgrass S. alterniflora plants, after 2–3 growing seasons, than nearby natural marshes. Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3182https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3182Tue, 06 Apr 2021 16:13:45 +0100Collected Evidence: Collected Evidence: Build barriers to protect littoral freshwater swamps from rising water levels and severe weatherWe found no studies that evaluated the effects, on vegetation, of building barriers to protect littoral freshwater swamps from rising water levels and severe weather.   ‘We found no studies’ means that we have not yet found any studies that have directly evaluated this action during our systematic journal and report searches. Therefore we have been unable to assess whether or not the action is effective or has any harmful impacts. Please get in touch if you know of such a study for this action.Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3183https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3183Tue, 06 Apr 2021 16:13:55 +0100Collected Evidence: Collected Evidence: Build barriers to protect littoral brackish/saline swamps from rising water levels and severe weatherWe found no studies that evaluated the effects, on vegetation, of building barriers to protect littoral brackish/saline swamps from rising water levels and severe weather.   ‘We found no studies’ means that we have not yet found any studies that have directly evaluated this action during our systematic journal and report searches. Therefore we have been unable to assess whether or not the action is effective or has any harmful impacts. Please get in touch if you know of such a study for this action.Collected Evidencehttps%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3184https%3A%2F%2Fwww.conservationevidence.com%2Factions%2F3184Tue, 06 Apr 2021 16:14:06 +0100
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What Works in Conservation

What Works in Conservation provides expert assessments of the effectiveness of actions, based on summarised evidence, in synopses. Subjects covered so far include amphibians, birds, mammals, forests, peatland and control of freshwater invasive species. More are in progress.

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